Scientists jailed over quake 'had case to answer'

The powerful earthquake devastated the Italian town of L'Aquila in April 2009.

AFP: Livio Anticoli, file

The Italian scientists convicted of manslaughter for falsely reassuring the public about the risk of the 2009 L'Aquila earthquake had a case to answer, according to an Australian expert.

The comments come in the face of an outpouring of concern from the scientific community claiming the scientists were being unfairly treated and the decision would inhibit scientists from expressing their views.

Four scientists, two engineers and a government official were sentenced to six years in prison for criminal manslaughter and causing criminal injury, with the prosecution arguing they gave "unclear, inconsistent" advice in the lead-up to the big quake.

Australian earthquake expert Professor Paul Somerville said he believed the prison sentences were not appropriate, but he was concerned about the actions of the scientists.

"The scientists do indeed have some serious questions to answer for," he said.

Professor Somerville, of the insurance industry-sponsored Risk Frontiers Natural Hazards Research Centre at Sydney's Macquarie University, pointed out that in the four months leading up to the large quake, there were a series of smaller quakes in the region.

He said most experts believe such a swarm can increase the likelihood of a larger quake, but this was not what was communicated to the residents.

Professor Somerville said locals had been sleeping out in their cars for fear of a large event after the smaller quakes started.

But, he said, they stopped doing this after being reassured by messages coming from a panel, made up of the convicted scientists and others, who met in the days leading up to the big quake.

"The problem is people were reassured it was not necessary to take the precautions they had been taking," Professor Somerville said.

The scientists cannot be blamed for not being able to predict the earthquake... But they should have said clearly that the swarm... elevated [the] risk."

Professor Paul Somerville

Scientific errors

Professor Somerville points to a number of scientific errors that were present in statements made publicly by the convicted experts, including Dr Bernardo De Bernardinis, a senior official in the Civil Protection Authority.

"Dr De Bernardinis, who is an expert in floods, not earthquakes, incorrectly stated the numerous earthquakes of the swarm were releasing stress and thereby inhibiting the occurrence of a larger earthquake," he said.

The case has drawn condemnation from international bodies including the American Geophysical Union, which said the risk of litigation may deter scientists from advising governments or even working in seismology and seismic risk assessments.

However, Professor Somerville said the scientists were never on trial for failing to predict the quake.

"The scientists cannot be blamed for not being able to predict the earthquake because the risk was always very low, even after the beginning of the swarm," he said.

"But they should have said clearly that the swarm ... elevated [the] risk."

Risk communication

Professor Somerville says seismologists at the time estimated the probability of a large earthquake in the days before the swarm began increased from one in 200,000 to one in 1,000 following two large foreshocks of the L'Aquila earthquake.

These are still very small numbers in an absolute sense, so it was true to say that a large quake was "unlikely".

Yet, it was also true to say the swarm increased the risk of a large quake several hundred-fold.

One way of communicating calls for calm, another calls for alarm.

Professor Somerville suggested earthquake scientists should stick to better communication of the numbers and leave it to society at large to decide their significance.

"The experts have to learn how to make carefully constructed probabilistic statements and then it's up to the decision-makers to use them as they see fit," he said.